GONNA MISS YA: The Yankees may rue the day they traded away young slugger Jesus Montero to Mariners for Michael Pineda (inset), because hitters like Montero, with Seattle manager Eric Wedge, left, and general manager Jack Zduriencik (right), can be as hard to find as top-notch starters, says The Post’s Joel Sherman. Photo: AP

We should start with this proviso: Just about every personnel expert I respect thinks the Yankees did very well in shipping Jesus Montero and Hector Noesi to the Mariners for Michael Pineda and Jose Campos.

In fact, quite a few of the executives thought it was an overwhelming triumph for the Yankees, namely because they view Pineda as an ace in training and Montero as a special bat, but one unqualified to play a position.

Yet, after all of these conversations, I still have big doubts if the Yankees made the right decision. They acted from the accepted trading playbook: If you can obtain an ace-type, you must do it. The No. 1 starter continues to be viewed as the Holy Grail of the sport.

But what might be lost is that great hitters are becoming as rare to find. Maybe it is about fewer illegal performance enhancers in the game or, perhaps, we have ushered in an era of better pitching. The result is that offensive numbers are down across the board. For example, slugging percentage dropped below .400 sport-wide in 2011 for the first time since 1992. Consider that just

28 players who qualified for the batting title last year reached at least a .500 slugging percentage compared with 47 five years ago.

Whether Montero can play in the field remains in dispute. But there is little doubt about his hitting. The consensus is that what you saw in his cameo last year — .328 average, .590 slugging percentage — reflects his ability. It is not a stretch of the imagination to think he would have become the Yankees’ No. 5 hitter as early as the 2012 campaign en route to becoming the long-term cleanup man behind Robinson Cano.

Still, the Yankees would argue they used an area of strength (offense/catcher) to address a weakness (high-end starting pitching). On the surface, this is accurate. Nevertheless, the Yankees’ offense is the young George Foreman: A mighty bully against weak foes, but something considerably less fierce against standout pitching.

It is intuitive to recognize all offenses grow less effective against better pitching. But the Yankees’ first-round elimination against the Tigers exemplified how few of their hitters can handle above-average pitching. In fact, the advanced metrics show only Cano and, to a lesser degree, Mark Teixeira performed well against top pitching last year. (Thanks to Derek Carty at Baseball Prospectus for doing the research.) Conversely, Curtis Granderson, Russell Martin, Nick Swisher, Brett Gardner and Alex Rodriguez struggled significantly against the better arms in the game.

My sense is Montero will be effective regardless of who pitches because he has elite bat speed, a willingness to hit to all fields (and to do so with power), and an ability, even at a young age, to make adjustments from at-bat to at-bat.

When I proposed this theory to an AL personnel man, he said he understood it, but “even if Montero produces those numbers, if he does so as a DH, you still have to trade him for a potential ace. If those numbers are produced as a catcher, then it is a different argument. But we just don’t think Montero can catch.”

Interestingly, the Yankees do. They don’t foresee Montero being confused with Yadier Molina, but they think he will be adequate. Here is the thing: Teams that receive big offense behind the plate, even from limited defensive catchers, tend to win. That probably is because there are so few strong-hitting catchers that if you have one, the offensive discrepancy against an opponent far outweighs the defensive deficiencies.

Over the past 20 years, Mike Piazza, Javy Lopez, Victor Martinez and, yes, Jorge Posada were all considered above-average offensively and below-average defensively, and — by and large — they played for successful teams. You can make a pretty good argument that the AL West title — and perhaps the AL pennant — came down to Angels manager Mike Scioscia, a former defensive stalwart as a catcher, growing disenchanted with Mike Napoli’s defensive work.

That led to Napoli becoming a vital member of the AL champion Rangers. The Angels finished 10 games behind Texas in the AL West and missed the playoffs, to some degree, because Jeff Mathis was a good defensive catcher, but he hit .174 with three homers — or as many as Napoli produced in just the playoffs.

There are many reasons why the Twins went from 94 wins in 2010 to 99 losses in 2011. But a huge one is this: Joe Mauer went from an .871 OPS catcher who played 137 games to a .729 OPS in 82 games.

Like with Napoli, teams constantly were trying to get Piazza, Lopez, Martinez and, yes, Posada out from behind the plate. And that probably will happen with Montero, as well. But teams — and pitchers — should learn to have greater tolerance when the offense is this special. For more than a decade I heard pitchers bellyache about Posada botching strikes or being bullheaded about pitch selection, but that always went silent on the days when he hit a three-run homer.

For the Yankees, maybe this will turn out like the three-team deal in which they gave up, among others, Ian Kennedy and received Granderson, and all the parties wound up happy. Maybe the talented Pineda does translate a strong 2011 rookie campaign into becoming CC Sabathia’s worthy wingman, a dominant No. 2 with No. 1 stuff. But let’s not act as if that is not at least as precarious as anything having to do with Montero. We can find a lot of one-shot wonders with stuff — think Mark Prior, Edinson Volquez, Fausto Carmona (or whatever his name is) — littered over the last decade.

Or here is another way to think of it: In five years, what is more likely, that Pineda is a No. 1 starter or Montero is a No. 4 hitter?